Fluid reservoir for a paint spray gun

ABSTRACT

The invention relates to a fluid reservoir for a paint spray gun, comprising a receptacle ( 1 ) and a lid that can be placed thereupon and is provided with a connecting element ( 3 ) in order to mount the fluid reservoir on the paint spray gun or an adapter. The receptacle ( 1 ) is provided with a ventilation hole ( 4 ) which can be sealed using a valve. In order to improve the tightness of the valve, said valve encompasses two valve seats for sealing the ventilation port ( 4 ), which are disposed one behind another in the direction of flow.

FIELD OF THE INVENTION

The invention relates to a fluid reservoir for a paint spray gun.

BACKGROUND OF THE INVENTION

Such a fluid reservoir is known from prior art, for instance, WO98/32539. This fluid reservoir is provided for one time use andcomprises a container of plastic and a lid that can be placed thereon toclose off the container. On the lid, connecting means are provided forplacing the fluid reservoir on and fastening it to a paint spray gun oran adapter mounted thereon. In this case, the fluid reservoir is placed“upside down” on the paint spray gun, i.e., with lid side down. Thepaint present in the fluid reservoir then flows by gravity downwardsinto the paint inlet channel of the paint spray gun. In order to allowthe gravity driven flow of paint, it is necessary for the pressure inthe interior and that in the environment to be equalized. In order toguarantee this equalization, a ventilation part that can be closed bymeans of an adhesive tape or a manually operable valve is made in thecontainer's bottom.

All the devices from prior art for closing the ventilation part haveproved inadequate with regard to their tightness. Even with a valvemechanism, it cannot be reliably assured that paint will not escapethrough the ventilation part when the paint filled fluid reservoir isset down on its base.

Starting from this point, the invention is based on the problem ofrefining the fluid reservoir as known from prior art such that a flow ofpaint through the ventilation part is reliably prevented.

SUMMARY OF THE INVENTION

This problem is solved by fluid reservoir with the characteristics ofClaim 1. Advantageous refinements of this fluid reservoir can be deducedfrom the subordinate claims.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will be explained in detail below on the basis of oneembodiment with reference to the appended drawing. The drawings show:

FIG. 1, oblique side view of a fluid reservoir according to theinvention;

FIG. 2, oblique representation of the container of the fluid reservoiraccording to the invention from FIG. 1, in a view from obliquely below;

FIG. 3, detail view of area Y from FIG. 2;

FIG. 4, sectional representation of a valve for closing the ventilationpart in the receptacle bottom of the fluid reservoir from FIG. 2,wherein the valve is shown in the closed position in FIG. 4(a) and inthe opened position in FIG. 4(b);

FIG. 5, side view of the fluid reservoir according to the invention,wherein the receptacle is represented in cross section and detail viewsof areas X and Y are shown;

FIG. 6, sectional representation of the fluid reservoir of FIG. 1 in thearea of the lid;

FIG. 7, top view onto an alternative embodiment of a valve for closingthe ventilation part in the receptacle bottom (FIG. 7 a) and sectionalrepresentations of this alternative embodiment along line A-A (FIG. 7 b)and along line B-B (FIG. 7 c), wherein the valve is shown in the openedposition;

FIG. 8, representation of the alternative embodiment of the valve, shownas in FIG. 7, but in the closed position of the valve.

DETAILED DESCRIPTION OF THE INVENTION

As shown in FIG. 1, the fluid reservoir according to the inventioncomprises a cup shaped receptacle 1 and a lid 2 that can be screwed ontoit by way of a thread 19. Thread 19 formed on the upper rim ofreceptacle 1 for screwing lid 2 on is recognizable in FIG. 2. On itsupper side, lid 2 has an outlet neck 20 with an outlet opening 19, notshown in FIG. 1. A connecting element 3 is formed on the outer side ofoutlet neck 20. Connecting element 3 serves for placing and fasteningthe fluid reservoir on a paint spray gun or on an adapter arrangedbetween the paint spray gun and the fluid reservoir. In the embodimentshown in the figures, connecting element 3 comprises a thread 21 and awedge shaped groove 22 that cooperate with corresponding connectingelements of the paint spray gun, namely a matching inside thread and apin for engagement in groove 22.

Receptacle 1 is cup shaped with a circular receptacle bottom 23 andsidewall 24 opening upward slightly conically, as is evident from FIG.2.

The fluid reservoir is shown in a side view in FIG. 5, whereinreceptacle I is shown in section. The central area of receptacle bottom23 is shown in detail view X of FIG. 5. A hollow cylindrical projection10, wall 29 of which projects vertically outward from receptacle bottom23, is formed on receptacle bottom 23. Projection 10 is integral withreceptacle bottom 23. Central axis A of hollow cylindrical projection 10is arranged concentrically to the central axis of receptacle 1. Aventilation part 4 is formed in receptacle bottom 23, likewiseconcentrically to axis A. Ventilation part 4 is enclosed by an annularwall 8. A radially running annular rib 17 is formed on outer side 9 ofwall 29. It is evident from the representation of FIG. 3 that aplurality of depressions 18, which are arranged segment by segment inthe radial direction with a distance between one another, are providedin outer side 9. Depressions 18 extend axially from upper edge 30 ofprojection 10 to roughly half the height of projection 10 (FIG. 4).Openings can also be provided instead of depressions 18.

As is illustrated in FIG. 5, two closure elements 5 are formed onto lid2, each via pull off tabs 25. Pull off tabs 25 are formed aspredetermined breakage points so that closure elements 5 can be tornmanually away from lid 2 without the aid of tools. Closure elements 5are each identical to the other, and serve to close ventilation part 4on the one hand and to close outlet opening 19 on the other.

As is evident from detail view Y in FIG. 5, closure element 5 has ahollow cylindrical base body 11 and a lid 26 formed integrally with it.In a central area, lid 26 is indented into the interior of base body 11,that is, downwards in the detail view Y of FIG. 1, in order to form aplug 12. A stopper 13 tapering conically downwards is formed on theunderside of this plug 12. The underside 27 of stopper 3 projects pastlower edge 28 of base body 11. Two annular grooves 15 and 16, runningparallel and apart from one another, are formed on the outer side ofhollow cylindrical base body 11.

One of the two closure elements 5 cooperates with projection 10 to forma valve for closure of ventilation part 4, with projection 10 projectingfrom receptacle bottom 23 forming the housing and closure element 5forming the valve cover. The valve is constructed here as a double seatvalve, with two valve seats arranged one after the other in thedirection of flow and separated from one another. Each valve seat hasits own sealing surface, 6 and 7, respectively. The cooperation ofclosure element 5 and projection 10 to form the valve with whichventilation part 4 can be closed off is shown in detail in FIG. 4. Forthis purpose, closure element 5 is pushed over projection 10, so thathollow cylindrical base body 11 embraces the cylindrical wall ofprojection 10. In order to guarantee a tight contact of closure element5 on projection 10, the inside diameter of hollow cylindrical base body11 and the outer diameter of hollow cylindrical projection 10 areroughly equally large.

The valve formed by closure element 5 and projection 10 can be fixed intwo valve positions by cooperation of grooves 15 and 16 on the innerside of base body 11 and annular rib 17 on the outer side of projection10. In the valve position shown in FIG. 4(a), annular rib 17 engageswith upper annular groove 15 and lower edge 28 of hollow cylindricalbase body 11 rests on receptacle bottom 23. At the same time, stopper 13engages with ventilation part 4. The outer surface of stopper 13 reststightly against wall 8 of ventilation part 4 in this case. In thismanner, a first valve seat with a first sealing surface 6 is formed. Atthe same time, a second sealing surface 7 separated from first sealingsurface 6 is formed by virtue of the fact that the inner side of basebody 1I rests tightly against outer wall 9 of hollow cylindricalprojection 10. In this valve position, ventilation part 4 is tightlyclosed by the first valve seat (which is formed by the engagement ofstopper 13 with ventilation part 4) on the one hand and, on the other,by way of the second valve seat (which is formed by the contact of innerside 14 of base body 11 with the lower periphery of outer wall 9). If asmall amount of paint were to flow out of ventilation part 4 through thefirst valve with first sealing surface 6, the further flow of paint outof receptacle 1 is prevented by the second valve seat.

To open ventilation part 4, closure element 5 can be brought into asecond valve position, as illustrated in FIG. 4(b). For this purpose,the closure element is raised upwards, that is, away from receptaclebottom 23, until annular rib 17 engages with lower annular groove 16(FIG. 4(b)). To facilitate this raising of closure element 5 from thefirst to the second valve position and to detach the initial seating ofannular rib 19 in upper annular groove 15, it is advantageous for lidpart 26 of closure element 5 to project laterally past base body 11. Onthe one hand, an easier gripping of the closure element on lid 26 ismade possible thereby, and on the other, the engagement of annular rib17 in upper annular groove 15 of lid 26 can be released, because theinside diameter in the area of base body 11 is enlarged by bending thisprojecting part of lid part 26 upwards.

In the second valve position shown in FIG. 4(b), stopper 13 isdisengaged from ventilation part 4 so that the latter is opened up. Atthe same time, the second valve seat is also released, since lower edge28 of base body 11 lies in the area of depressions 18 on the outer sideof projection 10 in this valve position, as is evident from FIG. 4(b),right side. In this position, it is possible for air to pass from theinterior of receptacle I through ventilation part 4 and through thepassageway formed between depressions 18 and inner side 14 of base body11.

The second closure element 5 formed on lid 2, which is formedidentically to the other closure element 5, can be used for closing offoutlet opening 19 on the connecting element of lid 2 in that thisclosure element 5 is first broken off lid 2 and then placed on outletneck 20. The inside diameter of base body 11 and the outside diameter ofoutlet neck 20 are matched to one another for this purpose, so thatinner side 14 of base body 11 rests tightly against the outer side ofneck 20, as shown in FIG. 6.

Another embodiment of a valve for closing off ventilation part isillustrated in FIG. 7. FIG. 7 a shows a top view of this valve which,just like the above described valve, has two valve seats arranged onebehind the other in the direction of flow. Identical components of thisvalve are furnished with the same reference numbers as in FIGS. 3 5. Asin the embodiment shown in those figures, projection 10 also forms thevalve housing in the valve shown in FIG. 7, and a closure element 5forms the valve cover. The valve is likewise constructed as a doublevalve with two valve seats separated from one another, each valve seathaving its own sealing surface 6 and 7, respectively. Closure element 5is pushed over projection 10 such that it grips it, with hollowcylindrical base body 11 embracing the cylindrical wall of projection10. In the center, closure element 5 has a cylindrical stopper 13, whichengages with ventilation part 4 in the closed valve position and formsfirst sealing surface 6 there. Second sealing surface 7 is again formedon outer wall 9 of projection 10, where inner surface 14 of closureelement base body 11 rests against it.

Unlike the embodiments of FIGS. 3-5, closure element 5 shown in FIG. 7is not seated on projection 10 via an engagement mechanism, but rathergrips it. Closure element 5 can be displaced between a first limitposition and a second limit position, with the valve being opened in thefirst limit position, as shown in FIGS. 7 a and 7 b, and closed in thesecond limit position, as shown in FIGS. 8 a and 8 b. An annular rib 17a is formed on the outer side of projection 10. An annular groove 15 ain closure element 5, which cooperates with annular rib 17 a to form twostops in the first and second valve position, is provided on the innersurface of hollow cylindrical base body 11. In the valve position shownin FIG. 7, the lower edge of annular groove 15 a rests against annularrib 17 a, and in the closed valve position shown in FIG. 8, the upperedge of annular groove 15 a rests against annular rib 17 a. Betweenthese two positions, closure element 5 is displaceable relative toprojection 10.

In an embodiment of the fluid reservoir not represented graphicallyhere, it is provided that ventilation part 4 is first closed off by athin membrane, and is then punctured into the first valve position onlyupon insertion of closure element 5 by pushing a sharp point formed onstopper 13 of closure element 5 through the thin membrane.

Due to the formation of two separate valve seats, each with a sealingsurface 6 or 7, respectively, a tight closure of ventilation part 4becomes possible with the fluid reservoir according to the invention.This closure is distinguished from measures for closing off theventilation part in the container's bottom that were known from priorart by better leak tightness. Ultimately this makes it possible to setthe container on the floor without paint present in the containerleaking out. It is thereby made possible, in particular, to mix paint inthe container before the container is then placed in the usual manner onthe paint spray gun. The valve for closing off the ventilation part isfurther distinguished by the fact that closure element 5 can easily beremoved manually from the container by pulling it off after undoing thesnap connection. This makes it possible for excess paint that was notconsumed in the painting process to flow out of ventilation part and berecycled if the container is held with the receptacle bottom facingdownwards.

In an alternative embodiment, not shown graphically here, ventilationpart 4 and projection 10 surrounding it is situated eccentricallyrelative to the longitudinal central axis of receptacle 1, i.e.,ventilation part 4 as well as central axis A of projection 10 areeccentric relative to receptacle bottom 23.

Furthermore, the valve for closing off ventilation part 4 can beconstructed such that it can be set to more than two valve positions.For this purpose it is provided, for instance, that more than twoannular grooves 15, 16 are arranged on the outer side of hollowcylindrical base body 11. As an alternative to a plurality of annulargrooves for forming a valve that can be locked in several positions, itis also possible for double annular grooves to be formed in parallel andwith a distance between one another.

1. Fluid reservoir for a paint spray gun with a receptacle (1) and a lid(2) that can be placed thereon, which has a connecting element (3) inorder to place the fluid reservoir on the paint spray gun or an adapter,wherein receptacle (1) has a ventilation part (4) that can be closed bymeans of a valve, characterized in that the valve for closure ofventilation part (4) has two valve seats arranged one behind the otherin the direction of flow.
 2. Fluid reservoir according to claim 1,characterized in that each valve seat has a sealing surface (6; 7),wherein these sealing surfaces (6; 7) are separated from one another. 3.Fluid reservoir according to claim 1 or 2, characterized in that thevalve comprises a valve housing arranged on the container and acorresponding closure element (5).
 4. Fluid reservoir according to claim3, characterized in that closure element (5) closes off ventilation part(4) in a first valve position, and in a second valve position allows anequalization of pressure between the interior of receptacle (1) and theenvironment.
 5. Fluid reservoir according to claim 3, characterized inthat the valve housing is formed from a hollow cylindrical projection(10) that is arranged on the receptacle wall, in particular, onreceptacle bottom (23), and that surrounds ventilation part (4). 6.Fluid reservoir according to claim 5, characterized in that sealingsurface (6) of the first valve seat is formed by wall (8) forming theventilation part, and in that sealing surface (7) of the second valveseat is formed by outer wall (9) of projection (10).
 7. Fluid reservoiraccording to claim 5 or 6, characterized in that closure element (5) canbe snapped into place on projection (10) via catch elements (15, 16,17).
 8. Fluid reservoir according to one of the preceding claims,characterized in that closure element (5) is formed from a hollowcylindrical base body (11) with a plug (12) which projects into theinterior of base body (11), and onto the end of which a stopper (13) forclosing off ventilation part (4) is formed.
 9. Fluid reservoir accordingto one of claims 3-5, characterized in that, with closure element (5)inserted, stopper (13) engages with ventilation part (4) in the firstvalve position and rests against wall (8) of ventilation part (4) toform first sealing surface (6), and simultaneously, inner surface (14)of base body (11) rests against outer wall (9) of projection (10) toform second sealing surface (7).
 10. Fluid reservoir according to claim8 or 9, characterized in that stopper (13) and ventilation part (4) areeach formed conically.
 11. Fluid reservoir according to one of claims8-10, characterized in that catch elements (15, 16, 17) that correspondto one another are formed on inner side (14) of base body (11) as wellas on outer wall (9) of projection (10), respectively, in order to fixclosure element (5) in one of the two valve positions.
 12. Fluidreservoir according to claim 5, characterized in that at least one,preferably a plurality, of depressions (18) or openings, each of whichprovides an air passage from the interior of receptacle (1) to theoutside with closure element (5) inserted in the second valve position,are formed in outer wall (9) of projection (10).
 13. Fluid reservoiraccording to one of the preceding claims, characterized in thatventilation part (4) is closed off by at least one membrane, which ispenetrated by closure element (5) in the first insertion of closureelement (5) into the first valve position.
 14. Fluid reservoir accordingto claim 13, characterized in that a point for penetrating the membraneis formed on closure element (5).
 15. Fluid reservoir according to oneof the preceding claims, characterized in that an outlet opening (19) isformed in connecting element (3) of lid (2), and in that closure element(5) is formed such that is also suitable for closing off this outletopening (19).
 16. Fluid reservoir according to one of the precedingclaims, characterized in that closure element (5) is first formed on lid(2) via a predetermined breakage point constructed as a pull-off tab(25), and can be torn off for closing ventilation part (4) or outletopening (19).
 17. Fluid reservoir according to claim 4, characterized inthat closure element (5) can be displaced relative to the valve housingfrom the first valve position to the second valve positions.
 18. Fluidreservoir according to claim 4 or 17, characterized in that closureelement (5) is seated on the valve housing such that it grips it.